Reversible snow plow attachment for wheeled vehicles

ABSTRACT

A reversible snow plow attachment for wheeled vehicles is provided in which a generally U-shaped frame is detachably connected to the vehicle by a trunnion mount which is located under the vehicle and to the rear of the front wheels. The frame includes straight drive bars on each side pivoted to the trunnion and extending forwardly outside of the &#39;&#39;&#39;&#39;cramp&#39;&#39;&#39;&#39; line of the front wheels. A mold board is pivotally connected to the frame to swing rearwardly to either side for reversible plowing. The mold board is especially long and arranged so that the resultant forces during plowing pass through or near to the center of traction of the wheels. Special arrangements are provided for high speed plowing with a long mold board including lateral abutment between the board and the frame for side plowing, and including a bridge structure on the back of the mold board which sandwiches the frame above and below and both supports the board longitudinally and restrains it from tipping forward or backward. The position of the trunnion mount is low and the drive bars transmit their force to a low point on the mold board. This improves the structural arrangement of the supporting elements against tipping of the board, and it minimizes the tendency of the board to lift the front wheels during plowing. Since the front end of the vehicle is not used for supporting the plow, the mold board can therefore be close to the wheels. Also, for vehicles having front end loader attachments, plowing can be done without removing the bucket, and the bucket can remain full, also improving traction. Standard hydraulics can be used for reversing the blade angle, and for lifting the blade.

United States Patent [191 Cooper 1 Feb. 18, 1975 I REVERSIBLE SNOW PLOW ATTACHMENT FOR WI-IEELED VEHICLES [76] Inventor: George R. Cooper, Bullock Rd.,

RD. 1, Slingerlands, NY. 12159 [22] Filed: Feb. 13, 1973 [21] Appl. No.: 332,180

[52] US. Cl 37/ll7.5, 172/80l, 37/DIG. 3, 37/50 [51] Int. Cl. E02f 3/76, E02f 3/62 [58] Field of Search 37/] 17.5, 41, 42 R, 42 VL, 37/50, DIG. 3; 172/276, 800-809 [56] References Cited UNITED STATES PATENTS 1,964,360 6/1934 Le Tourneau 37/50 X 2,191,323 2/1940 Richter 37/42 R 3,010,230 11/1961 Zubno 37/42 R 3,548,956 12/1970 Hochstetler.... 172/801 3.648782 3/1972 Mazzarins 172/804 3,655,000 4/1972 Winkler 172/804 3,661,214 5/1972 Peterson et al.... 172/809 3,665,622 5/1972 Lamb 37/1 17.5 3,779,408 12/1973 lvie 37/1 17.5

FOREIGN PATENTS OR APPLICATIONS 620,561 5/1961 Canada 172/805 523072 3/1956 Canada 37/D1G. 3 236.549 2/1960 Australia 172/800 Primary Examiner-Robert E. Bagwill Assistant Examiner-E. H. Eickholt [57] ABSTRACT A reversible snow plow attachment for wheeled vehicles is provided in which a generally U-shaped frame is detachably connected to the vehicle by a trunnion mount which is located under the vehicle and to the rear of the front wheels. The frame includes straight drive bars on each side pivoted to the trunnion and extending forwardly outside of the cramp' line of the front wheels. A mold board is pivotally connected to the frame to swing rearwardly to either side for reversible plowing. The mold board is especially long and arranged so that the resultant forces during plowing pass through or near to the center of traction of the wheels. Special arrangements are provided for high speed plowing with a long mold board including lateral abutment between the board and the frame for side plowing, and including a bridge structure on the back of the mold board which sandwiches the frame above and below and both supports the board longitudinally and restrains it from tipping forward or backward. The position of the trunnion mount is low and the drive bars transmit their force to a low point on the mold board. This improves the structural arrangement of the supporting elements against tipping of the board, and it minimizes the tendency of the board to lift the front wheels during plowing. Since the front end of the vehicle is not used for supporting the plow, the mold board can therefore be close to the wheels. Also, for vehicles having front end loader attachments, plowing can be done without removing the bucket, and the bucket can remain full, also improving traction. Standard hydraulics can be used for reversing the blade angle, and for lifting the blade.

8 Claims, 5 Drawing Figures PATENTED 81913 sum 1 or 3 mesas zz FIG. 4

PATENTEB FEB I 81975 SHEET 2 BF 3 REVERSIBLE SNOW PLOW ATTACHMENT FOR WI-IEELED VEHICLES BACKGROUND OF THE INVENTION The present invention relates to snow plowing attachments for vehicles. It has been found in the plowing of large turnpikes, airports, and the like that the maximum point of efficiency is when the plow need only take a cut of about 2 inches deep, and when it can operate at sufficiently high speeds to throw the snow a considerable distance to the side, i.e. at speeds above mph. Of course, the broader the path under such conditions, the better. Experience has shown that if the snow gets any deeper, wheeled vehicles cannot handle it at high speeds or with sufficiently large mold boards. Of course, crawler vehicles cannot operate fast enough. They are useful only for recovering from a crippling storm but not for maintaining the flow of traffic during a major storm. Therefore, the industry has been attempting for a number of years to lengthen mold boards and increase speeds, but the equipments hitherto available have had various serious draw-backs. The mountings for snow plows in general use are conventionally attached to the front end of the vehicle. With the mounting so positioned, however, inorder to provide sufficient support behind the mold board to resist the forces of high speed plowing, and to reduce the tendency of the blade to lift the front wheels, it has been necessary to place the blade well ahead of the mounting and hence well ahead of the wheels. This creates a long lever arm from the center of the vehicle on which the sideward forces act so as to throw the vehicle off line. The result is to limit the length of the mold board and the speed of operation. An object of the present invention is to increase both.

Another problem which is intensified as the speed of plowing increases, relates to tipping forces on the mold board. Resistance at the board cutting edge tends to tip the board over forward. Some plows areprovided with a spring release mechanism to permit such tipping, but modern highway and airport plowing is designed to make as clean a sweep as possible. No provision is made for forward tipping. The tendency to tip backward can also be a problem as the mold board recoils from the shock of resistance at high speeds. In order to withstand these tipping forces in the past, heavy strength members have sometimes been interconnected between the front end of a vehicle and the plow. This has been adequate to resist tipping but it makes reversing the angle of the blade difficult. Of course, the ability to reverse mold boardangle is important. The blade can only throw the snow a certain distance to the side of a road, and therefore, it often becomes important to be able to throw it toward the median strip of a divided highway. The equipment currently in use however, for reversibly mounting the mold board are typically a horizontal plate mounted on a support arm depending from the front end of the vehicle. The plate carries an upstanding pivot pin. The mold board is then adapted with a mating plate which is perforated to receive the pin. Such an arrangement permits reversing, but it has very poor resistance to tipping.

The present invention has as its primary object the provision of a snow plow attachment for vehicles which maximizes the mold board length permissible for a given vehicle operating at a given high speed. Among the further objects is the provision of such an attachment in which the blade angle is also easily reversed but yet the blade is ruggedly supported against tipping forces. Other objects will appear as the description proceeds.

BRIEF DESCRIPTION OF THE INVENTION In the accomplishment of the foregoing objects, in a preferred embodiment of my invention, I employ a generally U-shaped frame which fits around the front of the vehicle with the arms of the U, which form the drive bars of the frame, extending rearwardly and outside of the line of the front wheels of the vehicle in their fully turned position. A trunnion mount is provided at a low point under the vehicle secured to the main longitudinal strength members of the vehicle chassis and located to the rear of the front wheels. The drive bars are pivotally mounted on the trunnion. A mold board is mounted on the frame to pivot about a central, vertical axis to swing to an angle of 30 to either side for reversible plowing. A 36 foot mold board is used. Speeds of more than 25 mph for plowing are feasible.

A primary feature is the low pivot point and central connection for the drive bars and the straight line thrust to a low point on a mold board which extends well outside the line of the wheels in their fully turned position. The low thrust line and the central connection to the vehicle minimize the tendency of the plowing re action forces to lift the front wheels. In addition, they permit the mold board to be mounted as near as possible to the wheels. A particularly important feature relates to the relationship between the angle of the mold board, its length, and the center of traction of the vehicle. These are chosen so that the resultant force-s of plowing pass through or near to the center of traction of the vehicle. In this way, maximum plowing efficiency is attained and the plowing forces do not turn or swirve the vehicle.

Another feature relates to supporting the mold board against tipping forces and simultaneously bracing the board longitudinally. This is done by double bridge-like structure mounted on the back of the mold board. The bridges are horizontal and extend longitudinally, one near the lower part of the board and the other near the upper part. When the board is mounted on the frame, the two bridges sandwich the frame between them. If the board receives a tipping force it moves the bridge structure into contact with the frame. In this way, the

tipping forces are resisted by the frame and the bridge structures and not by the pivotal connection of the mold board to the frame.

Still another feature is that the front of the vehicle is left unencumbered by the snow plowing attachment. This means that a front end loader attachment on the vehicle can remain in place during snow plowing. This can be a convenience, but it also can be more than that. It can provide a cooperative relationship in the context of'snow plowing because the loader bucket can be left filled, and'depending upon its weight, equalize the traction between the front and rear wheels during plowing, Also a connection between the front end loader and the mold board can be employed to raise the mold board off the ground.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in front elevation of the snow plowing attachment of my invention;

FIG. 2 is a perspective view;

FIG. 3 is a plan view; FIG. 4 is a view in side elevation; and FIG. 5 is a diagramatic view illustrating the force relationships.

DETAILED DESCRIPTION OF THE INVENTION A preferred embodiment of my invention, selected for purposes of illustration, is shown in the accompanying drawings in which the snow plow attachment is adapted for attachment to a vehicle indicated at 10. The vehicle shown in FIGS. 1 and 2 is a Catapillar Wheel Loader which employs a 4-wheel drive and is capable of plowing at speeds up to 30 mph. A front end loading bucket, indicated at 12, is mounted on the vehicle in a conventional manner not shown.

The snow plowing attachment of my invention comprises a generally U-shaped support frame 14, having arms 16 adapted to fit around the front of the vehicle spaced outwardly of the wheels at their maximum position of turn or cramp angle. The arms 16 are provided with telescoping extension members 18 which are connected to the vehicle by means of a trunnion mount 20 which is secured at 22 to the longitudinal strength members of the chassis of the vehicle 10. The U-shaped frame 14 is thereby mounted to' pivot about the transverse horizontal axis of the trunnion mount 20. The forward portion of the U-shaped frame 14 is made up of rugged strength members formed into an isosceles triangle 24 terminating at an apex on the center line of the vehicle. Similarly, the arms 16 are reinforced by triangular elements 26 terminating with apeces to each side, and with the bases of the lateral triangles overlapping the lateral corners of the forward triangle 24. This construction provides an exceptionally strong frame for withstanding the forces involved in plowing with equipment as herein described.

A mold board 28 is mounted to pivot at 30 at the apex of the triangle 24. The mold board 28 is thereby adapted to swing to the rear on either side to an angle of 30 at which point a longitudinal thrust supporting buttress 32 on the rear of the mold board 28 comes into abuting relation with one ofthe sides of the frame triangle 24. Hydraulic jacks 34 are provided interconnected between the arms 16 and the mold board 28 to control the angular position of the mold board 28.

In order to reinforce the mold board 28 longitudinally and also to hold the board against tipping forces, a pair of horizontal bridge-like structures 36 and 38 are connected to the back of the mold board 28. The bridge structure 36 being connected to the upper portion of the rear of the mold board 28 and the bridge structure 38 being connected to the lower portion thereof. The bridge structures 36 and 38 are spaced apart to receive the forward triangular portion 24 of the frame 14 and to sandwich it there between. A wooden shock and wear resisting member 40 is mounted on the upper surface of bridge structure 38 and a pair of wooden shock and wear resisting members 42 are mounted on the upper surface of the frame 14, so as to fit closely to the frame and bridge structures and absorb the shock and wear of tilting forces on the mold board.

The pivotal connection between the mold board 28 and the apex of the triangular member 24 is relatively low and also the trunnion mount underneath the vehicle is likewise relatively low. Accordingly, the attachment mounted in this fashion, with straight drive arms 16 acting between a low point centrally of the vehicle and a low point of the mold board, provides optimum conditions for avoiding the tendency of the plowing attachment to lift the front wheels of the vehicle and also provides an optimum position for minimizing tilting forces on the mold board during plowing operations. Also, in order to resist such tilting forces as occur, the bridge structures acting through the shock and wear resistant members 40 and 42, hold the mold board 28 from tipping without transmitting the tipping forces directly to the pivot bearings of the mold board at 30. or at the hydraulic jacks 34.

By the arrangement of the invention shown, it is possible to employ an exceptionally long mold board and to operate for snow plowing at high speeds. in the present example, the mold board is 36 feet in length, and speeds up to 30 mph are practical for plowing in snow of 2 to 3 inches depth.

With the arrangement shown, there is an important relationship between the angle of the blade during plowing, the length of the blade, the resultant reaction forces of plowing, and the center of traction of the vehicle. In FIG. 5, I have shown these relationships diagramatically. In the prior art, a relatively small plow was employed located relatively distantly from the wheels. With such a plow, the resultant reaction forces of plowing act on the vehicle along a line passing substantially forward of the center of traction. The result of such an arrangement in the past, was to cause the operator to steer more or less toward the side of the road and to constantly cause the wheels of the vehicle to skid or crab along the road. It will be appreciated, of course, that such skidding and crabbing is highly undesirable because it means that maximum traction has been effectively lost. With the arrangement of the present invention, a longer mold board is used and it is set closer to the wheels of the vehicle. In this way, the line of the resultant reaction forces of plowing is brought closer to the center of traction of the vehicle as illustrated in FIG. 5. This substantially reduces the tendency of the plow to break the traction of the front wheels independently of the traction of the rear wheels, and thereby the most efficient conditions for traction exist.

It will be understood that the diagram represents a complex interrelationship of many factors. Thus, the direction of the projection of the snow varies with speed. Also, the increased accumulation of snow along the blade varies with speed. The moisture content of the snow effects the problem. Changes in loading also change the center of traction of the vehicle. Accordingly, it is not possible to calculate the relationships exactly and make sure that the resultant forces of plowing resistances will always pass through the center of traction. It is possible, however, to establish these relationships for certain expected conditions such as plowing 3 inches of dry snow, at 25 mph, with a 36 foot mold board, as I have illustrated. This is done by estimating the optimum blade angle and length, and then testing it in the field. If the vehicle then swirves during plowing under the designed conditions an appropriate adjustment of the blade angle and/or length is made to bring the resultant plowing resistance line in a direction to prevent the swirving, that is, more forward the center of traction of the vehicle.

With the arrangement shown, the front end of the vehicle is not used for mounting. the snow plow, and this means that a front end loading bucket can be left in place as in FlG. 2. In FIG. 2, the bucket is relatively low. It will be understood, however, that it can be raised, and the arms 16 and 18 can be telescoped to bring the mold board closer to the front wheels. Such an adjustment represents one of the ways that the resultant forces of plowing can be made to pass through the center of traction. Of course, filling the bucket also is another way to do it. By filling the bucket, the center of traction is shifted forward.

It also may be convenient to use the front end loader for lifting the mold board. This may be done by interconnecting chains 50 between bucket 12 and the frame 14 as may be seen in FIG. 2, and by employing hydraulic jacks 52 to lift the bucket 12.

Among the advantages of the arrangement of this invention is the ease and convenience of attachment. The vehicle can simply be driven into the U-shaped frame, and the frame can be attached to the trunnion mount in a matter of seconds. The trunnion mount itself is not difficult to attach, and once attached, it can be left in place because it does not interfere with normal use of the vehicle. A trunnion which extends fully across the vehicle, underneath, may not be necessary as long as hubs or pivots are available for the mount at each side, and the strength of a fully transverse trunnion is .not required.

In the embodiment shown, I employ a double thickness, undercurved cutting edge 44 for the mold board. This is particularly advantageous for high speed plowing. it will not ride up over the-snow but yet it prevents dangerous snagging on any solid projections of low profile which may intercept the path of the blade.

I claim:

1. A reversible snow plow attachment for a wheeled vehicle comprising;

pivotal connecting means on said vehicle arranged for pivotal motion about a transverse axis which is horizontal and located to the rear of the front wheels of said vehicle;

a frame of generally U-shape extending across and in front of the vehicle and rearwardly to said connecting means along each side outwardly of the line of the front wheels, when they are fully turned, said frame being connected to said connecting means;

a mold board adapted for attachment to said frame in snow plowing position in front of said vehicle;

means for pivotally connecting said board to said frame to pivot about a vertical axis to a rearwardly oblique angle on either side of the vehicle; and

means for both bracing said board along its length and for restraining it against pivoting about a horizontal axis in relation to said support frame including a pair of bridge structures mounted on and extending along the rear face of the board, and sandwiching the frame for a substantial distance to the rear of the board when the board is in position on the frame.

. 2. The reversible snow plow attachment for a wheeled vehicle of claim I further characterized by;

the board having an undercurved cutting edge for high speed snow plowing.

3. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by;

the frame and board constructed and arranged to meet in abutting relation from the pivotal connection to one side of the frame when the plow is pivoted fully to both sideplowing positions.

4. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by;

the board is substantially longer than twice the width of the vehicle.

S. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by;

auxiliary hydraulic power means and a power takeoff therefor associated with the vehicle, and a vertically acting hydraulic jack driven thereby and operationally arranged between the vehicle and the plow to raise the plow off the ground.

6. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by;

a front end loader on the vehicle, arranged with connectingmeans to the plow to raise the plow off the ground.

7. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by;

the support frame comprising a front portion of generally equilateral triangular construction with apex pointing forward, the sides of the frame comprise shallow triangles whose bases parallel the sides and whose apeces point outwardly, and the triangles of the sides and front portions substantially overlap at their respective adjacent corners.

8. The reversible snow plow attachment for a Wheeled vehicle of claim 1 further characterized by;

shock and abrasion resisting means positioned between said bridge structure and said frame. 

1. A reversible snow plow attachment for a wheeled vehicle comprising; pivotal connecting means on said vehicle arranged for pivotal motion about a transverse axis which is horizontal and located to the rear of the front wheels of said vehicle; a frame of generally U-shape extending across and in front of the vehicle and rearwardly to said connecting means along each side outwardly of the line of the front wheels, when they are fully turned, said frame being connected to said connecting means; a mold board adapted for attachment to said frame in snow plowing position in front of said vehicle; means for pivotally connecting said board to said frame to pivot about a vertical axis to a rearwardly oblique angle on either side of the vehicle; and means for both bracing said board along its length and for restraining it against pivoting about a horizontal axis in relation to said support frame including a pair of bridge structures mounted on and extending along the rear face of the board, and sandwiching the frame for a substantial distance to the rear of the board when the board is in position on the frame.
 2. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; the board having an undercurved cutting edge for high speed snow plowing.
 3. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; the frame and board constructed and arranged to meet in abutting relation from the pivotal connection to one side of the frame when the plow is pivoted fully to both sideplowing positions.
 4. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; the board is substantially longer than twice the width of the vehicle.
 5. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; auxiliary hydraulic power means and a power take-off therefor associated with the vehicle, and a Vertically acting hydraulic jack driven thereby and operationally arranged between the vehicle and the plow to raise the plow off the ground.
 6. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; a front end loader on the vehicle, arranged with connecting means to the plow to raise the plow off the ground.
 7. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; the support frame comprising a front portion of generally equilateral triangular construction with apex pointing forward, the sides of the frame comprise shallow triangles whose bases parallel the sides and whose apeces point outwardly, and the triangles of the sides and front portions substantially overlap at their respective adjacent corners.
 8. The reversible snow plow attachment for a wheeled vehicle of claim 1 further characterized by; shock and abrasion resisting means positioned between said bridge structure and said frame. 